1. Field of the Invention
This invention relates to a filter device which is disposed within a fuel tank such as a gasoline tank of an automobile.
2. Description of the Prior Art
A gasoline tank of an automobile is usually provided with a filter attached to the leading end of a suction pipe in order to prevent intake of impurities.
One conventional filter comprises a basket-shaped frame and a metallic net attached to the frame. Another conventional filter comprises a synthetic resin net instead of a metallic net, and likewise a synthetic resin frame integrally molded together with the net. At present, the latter type is used for the most part, in view of cost, manufacturing ease, and the like. Specific examples thereof are disclosed, for example, in Japanese Utility Model Publication Nos. SHO 52-37915, SHO 53-42840, and SHO 55-55784.
As described in the respective publications, these synthetic resin filters are superior to the metallic filters in respect of manufacturing ease, and the like. However, they have a shortcoming in that, because of their structure, the position at which fuel can be sucked in is relatively high. Therefore, it sometimes happens that fuel cannot be drawn in from the gasoline tank even though a considerable amount of fuel remains in the tank.
Furthermore, in recently designed automobile fuel tanks, the main body of the suction pump is disposed within the tank and the main body of the pump is provided with a filter. In this case, there arises the problem that the height of the filter makes it difficult to mount the pump main body and the conventional type of a filter becomes practically impossible to use.